Check the listing for details. Hewlett Packard HP 546A logic pulser Gen. 3. Condition: Seller refurbished. Listed at 121.33 USD. Hewlett Packard 546A Logic Pulser Gen. 3 In their life time these probes have undergone 3 minor revisions mainly in the cosmetic department, all revisions are functionally identical.The Pulser is a programable logic pulse injector, programed via the pulse button, it can inject single or strings of pulses either high or low and is able to detect if a node is high or low and if it is high it sinks the node low and if it is low then it sources the node high. A very clever and essential partner for the logic probeThe line of Hewlett Packard probes is virtually bullet proof, my personal set which I used constantly for at least 30 years and still use from time to time has withstood the test of time and is still within the manufacture's original specification, I will never part with them and i guess there are a lot of service engineers like me around that is why the probes are so scarce. I guess when I finally shuffle off my mortal coil they will find a good home. They will outlast me :)All items are genuine, original and made in the United States.This item has been fully tested and has undergone extensive checks without errors.it is well within original manufacturers specifications and is in 'as new' cosmetic condition.The pulser comes with 2 additional complimentary grabbers ( in case of loss or damage of the original ones)I will include user and service manuals on either a USB memory stick or a CD. In addition the USB or CD will contain lots of information on all other HP Probes and associated logic devices.I urge all potential buyers to compare my prices and service to any other identical items available elsewhere. Keep in mind availability, international postage, $ exchange rate, and not to forget GST. You will find that what I offer is more than favorableThere are, or will be, other probes and combination of probes available periodically as they become available. If I do not have what you need drop me a line and check back here on a regular basis. I have made it my mission to track down and make available the HP line of probes at tested and at affordable prices.If you need something that I don't have drop me a lineThis item ships FREE within Australia via Australia Post Express with tracking and signature, 1 to 2 days to most large cities an around 3 days to other places (rural areas may take bit longer)